WASTE WATER Solutions COD/BOD5 Reduction with ROTAMAT® Fine and Micro Screens Removal of particulate material from wastewater – Eco-ecient use of capital – Water pollution control through maximum COD/BOD5 reduction – Service water and irrigation water recovery – Suitable for use in river and sea outfall applications

The protection of our waters (rivers, lakes, seas) for us and our future generations is a challenge we all have to face. Since the budgets available are frequently limited, they have to be spent as efficiently and economically as possible whilst achieving the maximum benefit. This is particularly pertinent in rural areas of developing and emerging countries where the most commonly used worldwide biological wastewater treatment systems of the activated sludge process type are both inefficient and uneconomical. The disadvantages of such biological wastewater treatment systems are: ➤ High energy...

WASTE WATER Solutions Bahia Blanca, Argentina: Three ROTAMAT® Wedge Section Screens installed in the channel ensure odour-free dewatering and removal of the screenings and signicantly improve this river and sea outfall application The total ecological benefit achievable with mechanical treatment can be demonstrated when comparing the reduction of oxygen-consuming substances discharged into the receiving water course with the resultant reduction achieved by biological treatment plants, both with the same investment cost of 1 Mio. Euro. (See table below.) Mechanical treatment however provides even...

➤ HUBER Solutions for river and sea outfall applications – Mechanical-chemical wastewater treatment systems ➤ ➤ effluent quality waste containing plastic material, such as sanitary products tertiary sludge aerobic and anaerobic treatment (composting or digestion) Flow diagram: Combination of several treatment methods for further wastewater reuse compostable screenings discharge to a receiving water course (river and sea outfall) / irrigation / process water sludge-containing screenings composting, or disposal due to plastic material contents WASTE WATER Solutions discharge to a receiving water...

➤ River and Sea Outfall: HUBER Solution I ➤ ➤ COD reduction 5-10 % fine screen e = 1 mm Solution I: Mechanical treatment of raw wastewater The sludge which contains screenings separated from the raw wastewater by the mechanical fine screen is odourfree and discharged into a container. Due to the removal of all plastic material the resultant sludge must be disposed of, or alternatively may be composted after presorting. Wastewater screening with a 2 mm ROTAMAT® Rotary Drum Fine Screen Ro 2 Outdoor installation of a ROTAMAT® Rotary Drum Fine Screen Ro 2 with insulation Screened wastewater used...

➤ River and sea outfall: HUBER Solution II ➤ ➤ Solution II: Mechanical treatment with combined coarse and fine screening. With mechanical treatment alone, COD reductions of 10-30 % can be achieved. The preference when using fine screens (ROTAMAT® Membrane Screen RoMem or ROTAMAT® Rotary Drum Screen RoMesh®) is to utilise a square mesh screening medium. With the twodimensional design, very fine apertures and the defined separation size provided by the square mesh, it will prevent in particular fibres and hairs being washed through the mesh before the screen basket surface is cleaned. bordering...

Typical separation sizes are 6 – 3 mm for coarse screening and 1.0 – 0.2 mm for fine screening. Automatic periodic high-pressure washing at 120 bar (standard setting: twice a day) eliminates sedimentation on the screen basket (grease, oil). As a filtrate of such quality can be reused for irrigation or as process water, this further treatment process provides a sustainable solution to a further environmental problem. The use of a ROTAMAT® Membrane Screen RoMem liquid for fine screening permits additional treatment of the sludgy screenings. Due to the special screenings transport by pump fine screenings...

➤ River and sea outfall: HUBER Solution III ➤ ➤ COD reduction up to 50 % coarse screen e = 3 – 6 mm Solution III: Wastewater treatment through combined coarse/fine screening and micro screening. This combination is able to significantly reduce COD by 50 % and DS by up to 80 %. The subsequent micro screen produces a virtually solids-free effluent. The high filtrate quality allows for reuse of the effluent as service water, process water, or for irrigation purposes. The screenings separated by the fine and micro screen are fed into a wash press where they are dewatered, compacted and discharged...

➤ Short planning and implementation time ➤ In river and sea outfall applications for COD/BOD5 reduction Mechanical treatment stages provide the following benefits for planners and operators: ➤ Small space requirements ➤ Cost-eective solids removal, high-eciency COD/BOD5 reduction ➤ No need for a preliminary or secondary clarier ➤ Odour-free discharge of separated, compacted screenings ➤ Optional and easy retrot of a biological treatment stage WASTE WATER Solutions The screens can be used for extensive elimination of solids and oxygen-consuming suspended material. ➤ In developing countries for...